Boring head with axial adjustment means

ABSTRACT

A boring head with bit adjusting means. The head has a body having a shank portion and a transverse channel in the lower part thereof and a transverse hole therein intersecting the channel and at right angles thereto. A pair of bit mounting bases is slidably positioned in the channel and a transverse hole extends through the bases generally aligned with the transverse hole in said body. A bolt is rotatably mounted in one end of the transverse hole in the body, extending through the transverse hole in the bases and threaded into the other end of the transverse hole in the body, the hole in the bases is larger than the bolt for permitting some relative movement between the bases and the bolt. A bit is secured to each of the bases, one being at one end of one base and the other being at the other end of the other base. Wedge means is provided for adjusting the positions of the bases downwardly in the channel when the bolt is only gently tightened.

United States Patent [191 Mazoguchi 1 BORING HEAD WITH AxiAL ADJUSTMENTMEANS [76] Inventor: Sutemarj Mazoguchi, No.

l738-Kita, Tawara-cho, Nara, Japan [22] Filed: Apr.- 10, 1973 [21]-Appl. No.: 349,844

Related U.S. Application Data [62] Division of Ser. No. 239,647, March30, 1972, which is a division of Ser. No. 93,932, Dec. 1, 1970, Pat.

7/1965 Bader 408/146 [4 1 Feb. 26, 1974 Primary Examiner-Francis S.Husar Attorney, Agent, or Firm- Wenderoth. Lind & Ponack [57] ABSTRACT Aboring head with bit adjusting means. The head has a body having a shankportion and a transverse channel in the lower part thereof and atransverse hole therein intersecting the channel and at right anglesthereto. A pair of bit mounting bases is slidably positioned in thechannel and a transverse hole extends through the bases generallyaligned with the transverse hole in said body. A bolt is rotatablymounted in one end of the transverse hole in the body, extending throughthe transverse hole in the bases and threaded into the other end of thetransverse hole in the body, the hole in the bases is larger than thebolt for permitting some relative movement between the bases and the'bolt. A bit is secured to each of the bases, one being at one end ofone base and the other being at the other end of the other base. Wedgemeans is provided for adjusting the positions of the bases downwardly inthe channel when the bolt is only gently tightened.

1 Claim, 6 Drawing Figures PATENTEU FEB25 SHEET 1 or 3 BORING HEAD WITHAXIAL ADJUSTMENT MEANS This application is a division of applicationSer. No. 239,647, filed Mar. 30, 1972, which in turn is a divisional ofSer. No. 93,932, filed Dec. 1, 1970 and now US. Pat. No. 3,730,636,issued May 1, 1973.

This invention relates to a boring head for use in internal cutting, andmore particularly to a boring head having a bit which is easilyextendable and retractable.

In the conventional boring head the bit is adjustably secured directlyto the boring head by means of a screw, making it necessary whenadjusting the position of the bit to loosen the screw each time the bitis to be extended or retracted. Thus, the known boring head has adisadvantage in that it requires a great deal of effort to adjust thebit thereof.

The first object of this invention is to obviate the aforementionedconstructional defect of the conventional boring head, and to provide aboring head which is simple in construction and easy to operate.

The second object of this invention is to facilitate the adjustingoperation of the bit and also facilitate the determination of the fixedbit position by improving the fixing means for fixing the bit to theboring head.

The third object of this invention is to facilitate min ute adjustmentof the bit by 'means of micromotion of bit mounting tables fixed to theboring head.

Those objects mentioned hereinbefore are attainable by the improvement,combination and operation of each segment constituting this invention,and the preferred embodiments thereof will be illustrated in thedetailed description set forth hereinunder with reference to theaccompanying drawings.

Amendments and modifications with regard to details of the constructionare to be included in the claims. appearing hereinafter.

FIG. 1 is an elevation partially in longitudinal section, showing 'afirst embodiment of the boring head according to this invention.

loosely fitted in said traverse hole 17. This bolt 18 is intersects atright angles with said concave channel 14-,

FIG. 2 is a lateral view of the foregoing embodiment.

FIG. 3 is a bottom view of the foregoing embodiment.

FIG. 4 is an elevation partially in longitudinal section,

showing a second embodiment of this invention.

FIG. 5 is a lateral view partially in longitudinal section of theforegoing embodiment.

FIG. 6 is a cross sectional view taken on the line 6-6 in FIG. 5. In theembodiment shown in FIGS. 1 to 3, the numeral ll designates a boringhead body having a shank 12 with a tapering, straight or any otherarbitrary shape. In the lower part of the boring head body 11 is formeda concave channel 14 traversing said body 11, the center of said concavechannel 14 coinciding with that of the axis of the body 11, both ends ofsaid concave channel 14 being open on the peripheral surface of the body11.

A pair of bit mounting bases 15 are slidably fitted inside the concavechannel 14. On the confronting faces of these mounting bases 15 areformed traverse zigzag ridges 16 slidably engaging with each other, saidtwo mounting bases 15 with the zigzag ridges l6 engaging with each otherbeing fitted into the concave channel 14 so as to be smoothly slidablebetween both lateral sides of said channel 14. I

In each of the mounting bases 15 is formed a traverse hole, a fixingbolt 18 attached to the body 11 being and is screwed into a threadedportion 20 of hole 19 on one side of channel 14. The head 21 of the bolt18 is fitted into a large-calibered bore 22 on the outside end of thehole 19. On the outside of said head 21 is formed a polygonal bore 23for engagement by a revolving tool. large-calibered The numeral 24designates a pair of diametrically opposed concavities formed in theupper part of both ends of the concave channel 14, the lower parts ofthe concavities 24 communicating with the concave channel 14, the upperfaces 25 of said concavities 24 being inclined downwardly towards theback thereof, as shown in FIG. 1.

The numeral 26 designates a wedge member fitted into each of theconcavities 24, the upper edge 27 of said wedge member 26 being inclinedso that it fits against the upper face 25 of each concavity 24, theunderside 28 thereof being horizontal so as to fit against the upperface of each bit mounting base 15. Moreover said underside 28 ispositioned so that part of it will extend over the upper face of eachmounting base 15, as shown in FIG. 2. I i

The numeral 29 designates a bolt which is loosely fitted into a hole 30provided in each wedge member 26, said bolt 29 being screwed into athreaded hole 31 provided at the back of the concavity 24, the head 32of each bolt 29 being loosely fitted inside a largecalibered bore 33formed on the outside end of the bore 30. The parts are so arranged thatsaid head 32 will be pressed against the bottom of the largecaliberedbore 33 through a washer 34. A coil spring 36 is fitted between alarge-calibered bore 35 formed on the inside end of the hole 30 and theback of the concavity 24, said coil spring 36 being externally fittedaround the bolt 29, the outer end of the spring 36 being pressed againstthe bottom of the large-calibrated bore 35 through a washer 36.Furthermore, in the aforementioned head 32 is formed a polygonalconcavity 37 for engagement with a revolving tool as shown in FIG. 2.The numeral 38 designates a bit secured by a bolt 39 in a concavity 42at the opposite ends of the mounting bases 15.

The numeral 40 designates scales provided on the underside of the body11, said scales 40 being formed along both sides of the concave channel14 to show the position of an indicator 41 provided on the lateral sideof each bit mounting base 15.

In the first embodiment of this invention, each bit mounting base 15 isfreely slidable inside the concave channel 14 when'the bolt 18 isloosened, and the amount each bit 38 extends beyond the lateral sides ofthe body 11 is freely adjustable by sliding traversely each mountingbase 15 along the zigzag ridges 14 inside the concave channel 14, theposition of each bit 38 being accurately determinable by setting theindicator on the mounting base 15 on the scale 40.

If the wedge member 26 is moved toward the back of the concavity 24 byscrewing each bolt 29 inwardly, when the bit mounting bases 15 have beenstabilized by gently tightening the bolt 18, the upper faces of themounting bases are contacted by the undersides 28 of the wedge members26 and the inclined upper edge 27 of the wedge member 26 slidesobliquely downwardly along the inclined upper face 25 of the concavity24, as a result of which the lower part of each wedge member 26gradually presses each mounting base downwardly, thereby making possibleminute adjustment of the amount of the downward extensions of the bit38.

Both bit mounting bases15 are tightly engaged at both sides of theconcave channel 14 when the bolt 18 is tightened after adjustment of theposition of said bases 15 as described hereinbefore. In this state, theboring head body 11 is attached to the main shaft of a taper shankboring machine for the boring operation.

FIGS. 4 to 6 show that the transverse minute adjustment of the bit iseasily carried out in the second embodiment of this invention.

In FIGS. 4 to 6, the numeral 51 designates a boring head body havingthereon shank 52 with a tapering, straight, or any other arbitraryshape, a dovetail channel 53 being traversely formed in the lower partof the body 51. The numeral 54 designates a bit mounting base having adovetail protrusion 55 integrally formed on the upper part thereof whichis slidably fitted into the aforementioned dovetail channel 53, ahelical rack gear 56 being formed on said protrusion 55.

In the body 51 is formed a transverse hole 57 positioned above thedovetail channel 53 and crossing said channel at right angles thereto,the central lower part of the transverse hole 57 communicating with thecentral part of the dovetail channel 53. Inside the transverse hole 57is slidably fitted a sliding element 58, a key 60 axially provided onthe upper side of the transverse hole 57 being slidably fitted into akey groove 59 on the upper side of the sliding element 58, so that saidsliding element 58 can accurately move along the axis of of thetransverse hole 57. Furthermore, on the underside of the sliding element58 is formed a helical rack gear 61 in mesh with the helical rack gear56.

The head 64 of a bolt 63 is rotatably fitted into an annular member 62secured over one end of the transverse hole 57, a polygonal concavity 67for engagement with a revolving tool being formed on the outside of saidhead 64. The bolt 63 is concentric with the transverse hole 57 and isscrewed into a threaded hole 65 formed in the sliding element 58. Alarge-calibered bore 66 is formed in the transverse hole at the end overwhich the annular member 62 is secured, and a flange 68 concentricallyformed at the base of the head 64 of the bolt 63 being supported on theinner end of the large-calibered bore 66 through washers 69 and 70. Theother end of the transverse hole 57 is closed by a lid 71 thereover.

The numeral 72 designates a bit fixed to the external end of a bolt 73,said bolt 73 being screwed into a threaded hole 74 formed obliquely inthe lower part of one end of the bit mounting base 54 and secured inposition with a setscrew 75.

In the second embodiment, as indicated in the drawings, if the bolt 63is revolved by engaging a revolving tool in the concavity 67 of the bolt63 with the helical rack gear 56 and the helical rack gear 61 of thesliding element 58 meshing with each other, then the sliding element 58moves in the axial direction, being prevented from revolving. As aresult, the mounting base 54 having the protrusion 55 which engages withthe sliding element 58 moves along the dovetail channel 53, therebyaltering the amount of lateral extension of the bit 72. Since thetransversal movement of the mounting base 54 is extremely small ascompared with the amount of rotation of the bolt 63, the amount the bit72 extends can be very finely adjusted. If the bolt 63 is revolved inthe same direction continuously, the sliding element 58 is ultimatelybrought into contact with the lid 71 as shown by the broken line (a) inFIG. 5, the helical rack gear of the sliding element 58 being completelydisengaged from the helical rack gear 56 on the protrusion 55.

In this condition, the bit mounting base 54 becomes slidableindependently of the bolt 63, thereby making it possible to move themounting base 54 a large distance.

After the position of the bit 72 has been changed to a large extent bydisengaging the helical rack gear 61 from the helical rack gear 56 asdescribed hereinbefore, minute adjustment can again be carried out byrevolving the bolt 63, thereby moving the sliding element 58 toward theprotrusion 55 so that the rack gears 61 and 56 can mesh with each other.Therefore, in this embodiment, both minute adjustment and large-scalemovement of the position of the bit are possible.

I claim:

l. A boring head comprising a body having a shank portion and atransverse channel in the lower part thereof and a transverse holetherein intersecting the channel and at right angles thereto, a pair ofbit mounting bases slidably positioned in said channel and havinginterengaging longitudinally extending ridges and grooves on the opposedengaging lateral faces of said bases, a transverse hole through saidbases generally aligned with said transverse hole in said body, a boltrotatably mounted in one end of said transverse hole in said body,extending through the transverse hole in said bases and threaded intothe other end of said transverse hole in said body, said hole in saidbases being larger than said bolt for permitting some relative movementbetween said bases and said bolt, a bit secured to each of the bases,one being at one end of one base and the other being at the other end ofthe other base, said body further having diametrally opposite wedgeshaped recesses therein above said transverse channel and openingdownwardly into said transverse channel, and said boring head furthercomprising wedge shaped members in said recesses and movable into saidrecesses with movement into said recesses causing the lower edges ofsaid wedge shaped members to move downwardly toward said transversechannel, said wedge shaped members having bolts therethrough threadedinto said body for urging said wedge shaped members into saidrecesseswhen said bolts are turned, whereby said bolt extending throughsaid transverse hole can be gently tightened to stabilize said bases atdesired positions along said transverse channel, and said wedge shapedmembers can be moved into said recesses to urge said bases downwardly todesired positions, and thereafter said bolt in said transverse hole canbe tightened firmly to hold said bases in the desired positions. 8 III33 3? UNITED STATES PATENT OFFICE I CERTIFICATE (H CORRECTION Patent No.3,794, 437 v Dated February 26, 1974 Inventor) SUTEMYARU MIZOGUCHI It iscertified that error appears in the above-identified patent and thatsaid Letters Patent are hereby corrected as shown below:

On the title page, item [76] for the inventor'e surname,

read MIZOGUCHI instead of MAZOGUCHI.

Signed and sealed this" 2nd day. of July 1974,

(SEAL) Attest:

EDWARD M. FLETCHER,'JR. I C.MARSHALL DANN Attesting Officer Commissionerof Patents

1. A boring head comprising a body having a shank portion and atransverse channel in the lower part thereof and a transverse holetherein intersecting the channel and at right angles thereto, a pair ofbit mounting bases slidably positioned in said channel and havinginterengaging longitudinally extending ridges and grooves on the opposedengaging lateral faces of said bases, a transverse hole through saidbases generally aligned with said transverse hole in said body, a boltrotatably mounted in one end of said transverse hole in said body,extending through the transverse hole in said bases and threaded intothe other end of said transverse hole in said body, said hole in saidbases being larger than said bolt for permitting some relative movementbetween said bases and said bolt, a bit secured to each of the bases,one being at one end of one base and the other being at the other end ofthe other base, said body further having diametrally opposite wedgeshaped recesses therein above said transverse channel and openingdownwardly into said transverse channel, and said boring head furthercomprising wedge shaped members in said recesses and movable into saidrecesses with movement into said recesses causing the lower edges ofsaid wedge shaped members to move downwardly toward said transversechannel, said wedge shaped members having bolts therethrough threadedinto said body for urging said wedge shaped members into said recesseswhen said bolts are turned, whereby said bolt extending through saidtransverse hole can be gently tightened to stabilize said bases atdesired positions along said transverse channel, and said wedge shapedmembers can be moved into said recesses to urge said bases downwardly todesired positions, and thereafter said bolt in said transverse hole canbe tightened firmly to hold said bases in the desired positions.